After the prints have been fixed they are washed exactly as are prints on albumenised paper.
This may be a good place to give a word or two of caution.
Absolute cleanliness in manipulation is quite as necessary in the case of prints on Alpha paper as in the case of prints on albumenised paper. The dishes must be most carefully washed before operations are com menced, and on no account must a drop of one bath be allowed to get into another.
The prints must be kept in continual motion in all the solutions and also in all the washing waters, otherwise irregularity of tone and impure whites will result.
Prints which show large expanses of white, especially vignettes, should be developed before others, so that they may have the advantage of freshly-mixed developer.
After the final washing the prints may be mounted in the same manner as albumenised prints, and rolled or burnished in the usual way.
A beautiful enamel surface may he obtained in the following manner : A piece of glass somewhat larger than the print is thoroughly cleaned. Powered talc, commonly known as French chalk, is now dusted over one surface of the glass. It is then polished off with a piece of dry flannel. The wet print is placed face downwards on the glass and a squeegee is gently passed over the hack of it to expel the moisture. The whole is placed on one side to dry in a warm room. When dry the print may easily be stripped off the glass. When it is removed it will be found that it has a splendid surface.
If it be desired to mount such prints so as to retain the full gloss, the following method is pursued : On the back of the prints upon the glass, when they have become about half dry, there is pasted with thick starch a piece of "three sheet board." When the whole
is dry the print will strip, as in the former case, but will of course come off attached to the thin board. This thin board may be attached to an ordinary mount with glue or mounting solution.
By pursuing a far simpler course a surface almost equal to "enamel" is obtained.
On to the back of prints when half dried on the glasses is brushed some very thick starch. The prints are then allowed to dry and are stripped from the glass. For each print an ordinary mount is taken. It is damped on one surface with a wet sponge. The back of the print is placed in contact with it, and the mount and print together are passed through the rolling press cold. Perfect adhesion of the print to the mount will ensue.
Alpha Opal Plates.
Positives on " opal " glass have a most charming effect. The absolute purity of the white of the matt-surface of the glass is like alabaster. There are various methods whereby prints on opal glass may be obtained, but the one to which we now refer has certain advantages over others. In regard to briefness of exposure and pelma nence of results it has precisely the same advantages that the Alpha paper has, whilst it is the only process that we know of in which the positives may be toned to any colour that is desired, exactly as silver prints are.
If the opals are to be viewed as prints by reflected light the manipulations are precisely the same as for the paper, except that, in the case of plates, it is of course possible to have but one in a dish at a time.
If they are to be viewed as transparencies hung up against a window or in some such position they must be somewhat more fully developed than in the other case.